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Döring, Nicola; Lehmann, Stephan; Schumann-Doermer, Claudia
Contraception in the German-language Wikipedia: a content and quality analysis :
Verhütung in der deutschsprachigen Wikipedia: eine Inhalts- und Qualitätsanalyse. - In: Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz, ISSN 1437-1588, Bd. 65 (2022), 6, S. 706-717

https://doi.org/10.1007/s00103-022-03537-8
Dölker, Eva-Maria; Lau, Stephan; Bernhard, Maria Anne; Haueisen, Jens
Perception thresholds and qualitative perceptions for electrocutaneous stimulation. - In: Scientific reports, ISSN 2045-2322, Bd. 12 (2022), 7335, S. 1-12

Our long-term goal is the development of a wearable warning system that uses electrocutaneous stimulation. To find appropriate stimulation parameters and electrode configurations, we investigate perception amplitude thresholds and qualitative perceptions of electrocutaneous stimulation for varying pulse widths, electrode sizes, and electrode positions. The upper right arm was stimulated in 81 healthy volunteers with biphasic rectangular current pulses varying between 20 and 2000 μs. We determined perception, attention, and intolerance thresholds and the corresponding qualitative perceptions for 8 electrode pairs distributed around the upper arm. For a pulse width of 150 μs, we find median values of 3.5, 6.9, and 13.8 mA for perception, attention, and intolerance thresholds, respectively. All thresholds decrease with increasing pulse width. Lateral electrode positions have higher intolerance thresholds than medial electrode positions, but perception and attention threshold are not significantly different across electrode positions. Electrode size between 15 × 15 mm2 and 40 × 40 mm2 has no significant influence on the thresholds. Knocking is the prevailing perception for perception and attention thresholds while mostly muscle twitching, pinching, and stinging are reported at the intolerance threshold. Biphasic stimulation pulse widths between 150 μs and 250 μs are suitable for electric warning wearables. Within the given practical limits at the upper arm, electrode size, inter-electrode distance, and electrode position are flexible parameters of electric warning wearables. Our investigations provide the basis for electric warning wearables.



https://doi.org/10.1038/s41598-022-10708-9
Labus Zlatanovic, Danka; Bergmann, Jean Pierre; Balos, Sebastian; Gräzel, Michael; Pejic, Dragan; Sovilj, Platon; Goel, Saurav
Influence of rotational speed on the electrical and mechanical properties of the friction stir spot welded aluminium alloy sheets. - In: Welding in the world, ISSN 1878-6669, Bd. 66 (2022), 6, S. 1179-1190

An efficient and productive joining technique to weld aluminium has become a priority challenge for promoting the use of aluminium in the electrical industry. One of the challenges is to obtain welds with superior mechanical properties with the consistent quality of weld surface as well as low electrical resistance. In this paper, the influence of rotational speed during the friction stir spot welding of AA 5754-H111 was studied to analyse the mechanical and electrical properties of the welds. The results from two rotational speeds (1000 rpm and 4500 rpm) are presented and compared to the base material. It was observed that the samples welded at 1000 rpm showed a higher average shear failure load (˜ 1.1 kN) compared to the samples welded at 4500 rpm (˜ 0.94 kN). The microhardness of the samples welded at 1000 rpm was higher than that of the base material, while the microhardness of samples welded at 4500 rpm was lower. It was also found that the friction welded sheets, regardless of the rotational speed used, showed increased electrical resistance compared to the base material, albeit this increase for the samples welded at 1000 rpm was about 42%, compared to samples welded at 4500 rpm where this increase was just 14%.



https://doi.org/10.1007/s40194-022-01267-8
Link, Steffen; Dimitrova, Anna; Krischok, Stefan; Ivanov, Svetlozar
Reversible sodiation of electrochemically deposited binder- and conducting additive-free Si-O-C composite layers. - In: Energy technology, ISSN 2194-4296, Bd. 10 (2022), 5, 2101164, S. 1-9

Binder- and conducting additive-free Si-O-C composite layers are deposited electrochemically under potentiostatic conditions from sulfolane-based organic electrolyte. Quartz crystal microbalance with damping monitoring is used for evaluation of the layer growth and its physical properties. The sodiation-desodiation performance of the material is afterward explored in Na-ion electrolyte. In terms of specific capacity, rate capability, and long-term electrochemical stability, the experiments confirm the advantages of applying the electrochemically formed Si-O-C structure as anode for Na-ion batteries. The material displays high (722 mAh g^-1) initial reversible capacity at j = 70 mA g^-1 and preserves stable long-term capacity of 540 mAh g^-1 for at least 400 galvanostatic cycles, measured at j = 150 mA g^-1. The observed high performance can be attributed to its improved mechanical stability and accelerated Na-ion transport in the porous anode structure. The origin of the material electroactivity is revealed based on X-Ray photoelectron spectroscopic analysis of pristine (as deposited), sodiated, and desodiated Si-O-C layers. The evaluation of the spectroscopic data indicates reversible activity of the material due to the complex contribution of carbon and silicon redox centers.



https://doi.org/10.1002/ente.202101164
Tomova, Mihaela Todorova; Hofmann, Martin; Mäder, Patrick
SEOSS-Queries - a software engineering dataset for text-to-SQL and question answering tasks. - In: Data in Brief, ISSN 2352-3409, Bd. 42 (2022), 108211, S. 1-11

https://doi.org/10.1016/j.dib.2022.108211
Bača, Martin; Brauer, Dana; Klett, Maren; Fernekorn, Uta; Singh, Sukhdeep; Hampl, Jörg; Groß, Gregor Alexander; Mai, Patrick; Friedel, Karin; Schober, Andreas
Automated analysis of acetaminophen toxicity on 3D HepaRG cell culture in microbioreactor. - In: Bioengineering, ISSN 2306-5354, Bd. 9 (2022), 5, 196, S. 1-16

Real-time monitoring of bioanalytes in organotypic cell cultivation devices is a major research challenge in establishing stand-alone diagnostic systems. Presently, no general technical facility is available that offers a plug-in system for bioanalytics in diversely available organotypic culture models. Therefore, each analytical device has to be tuned according to the microfluidic and interface environment of the 3D in vitro system. Herein, we report the design and function of a 3D automated culture and analysis device (3D-ACAD) which actively perfuses a custom-made 3D microbioreactor, samples the culture medium and simultaneously performs capillary-based flow ELISA. A microstructured MatriGrid® has been explored as a 3D scaffold for culturing HepaRG cells, with albumin investigated as a bioanalytical marker using flow ELISA. We investigated the effect of acetaminophen (APAP) on the albumin secretion of HepaRG cells over 96 h and compared this with the albumin secretion of 2D monolayer HepaRG cultures. Automated on-line monitoring of albumin secretion in the 3D in vitro mode revealed that the application of hepatotoxic drug-like APAP results in decreased albumin secretion. Furthermore, a higher sensitivity of the HepaRG cell culture in the automated 3D-ACAD system to APAP was observed compared to HepaRG cells cultivated as a monolayer. The results support the use of the 3D-ACAD model as a stand-alone device, working in real time and capable of analyzing the condition of the cell culture by measuring a functional analyte. Information obtained from our system is compared with conventional cell culture and plate ELISA, the results of which are presented herein.



https://doi.org/10.3390/bioengineering9050196
Beliautsou, Aleksandra; Beliautsou, Viktar; Zimmermann, Armin
Colored Petri net modelling and evaluation of drone inspection methods for distribution networks. - In: Sensors, ISSN 1424-8220, Bd. 22 (2022), 9, 3418, S. 1-20

https://doi.org/10.3390/s22093418
Weise, Konstantin; Müller, Erik; Poßner, Lucas; Knösche, Thomas R.
Comparison of the performance and reliability between improved sampling strategies for polynomial chaos expansion. - In: Mathematical biosciences and engineering, ISSN 1551-0018, Bd. 19 (2022), 8, S. 7425-7480

As uncertainty and sensitivity analysis of complex models grows ever more important, the difficulty of their timely realizations highlights a need for more efficient numerical operations. Non-intrusive Polynomial Chaos methods are highly efficient and accurate methods of mapping input-output relationships to investigate complex models. There is substantial potential to increase the efficacy of the method regarding the selected sampling scheme. We examine state-of-the-art sampling schemes categorized in space-filling-optimal designs such as Latin Hypercube sampling and L1-optimal sampling and compare their empirical performance against standard random sampling. The analysis was performed in the context of L1 minimization using the least-angle regression algorithm to fit the GPCE regression models. Due to the random nature of the sampling schemes, we compared different sampling approaches using statistical stability measures and evaluated the success rates to construct a surrogate model with relative errors of < 0.1 %, < 1 %, and < 10 %, respectively. The sampling schemes are thoroughly investigated by evaluating the y of surrogate models constructed for various distinct test cases, which represent different problem classes covering low, medium and high dimensional problems. Finally, the sampling schemes are tested on an application example to estimate the sensitivity of the self-impedance of a probe that is used to measure the impedance of biological tissues at different frequencies. We observed strong differences in the convergence properties of the methods between the analyzed test functions.



https://doi.org/10.3934/mbe.2022351
Adekitan, Aderibigbe Israel;
Improving the computational accuracy of the dynamic electro-geometrical model using numerical solutions. - In: Scientific reports, ISSN 2045-2322, Bd. 12 (2022), 5742, S. 1-13

The dynamic electro-geometrical model has been applied in various studies to investigate the probability of a lightning strike to parts of a structure. The numerical computation of the dynamic electro-geometrical model (DEGM) follows an iterative step by determining lightning strike points from above to a point on a structure of interest. This computation is often time-consuming and requires extensive computational resources. This study delves into the inner workings of DEGM striking distance computation. It highlights sources of computational numerical errors, such as the effect of the discretisation size. It proposes ways to eliminate such by using a conversion factor while also significantly reducing computation time from more than 14 h to approximately 6 min for a cuboid structure by eliminating ground surface points. The performance of the proposed improved DEGM (IDEGM) was investigated using a floating roof tank and a cuboid structure with a central air termination, and an interception efficiency of 61% was achieved. An alternative case using catenary wires with a total lightning interception efficiency of 99.1% was also implemented. The percentage strike probability for the cases considered shows a close approximation to published results, and this confirms the accuracy of the implemented model. The IDEGM has the benefit of generating results with a significantly reduced computation time of just a few minutes as compared to several hours in previous models.



https://doi.org/10.1038/s41598-022-09674-z
Xu, Rui; Zeng, Zhiqiang; Lei, Yong
Well-defined nanostructuring with designable anodic aluminum oxide template. - In: Nature Communications, ISSN 2041-1723, Bd. 13 (2022), 2435, S. 1-11

Well-defined nanostructuring over size, shape, spatial configuration, and multi-combination is a feasible concept to reach unique properties of nanostructure arrays, while satisfying such broad and stringent requirements with conventional techniques is challenging. Here, we report designable anodic aluminium oxide templates to address this challenge by achieving well-defined pore features within templates in terms of in-plane and out-of-plane shape, size, spatial configuration, and pore combination. The structural designability of template pores arises from designing of unequal aluminium anodization rates at different anodization voltages, and further relies on a systematic blueprint guiding pore diversification. Starting from the designable templates, we realize a series of nanostructures that inherit equal structural controllability relative to their template counterparts. Proof-of-concept applications based on such nanostructures demonstrate boosted performance. In light of the broad selectivity and high controllability, designable templates will provide a useful platform for well-defined nanostructuring.



https://doi.org/10.1038/s41467-022-30137-6